Some of the most successful people swear by the power of cold showers to start their day. Life Coach Tony Robbins never starts his morning without a freezing cold plunge in 57 F water. So, what’s the fuss? Cold water helps us become more alert, less stressed, and more happy and can act as a powerful motivator if we’re feeling tired or down.

“I do it both as a mental discipline, and also because it stimulates the blood flow of the lymph nodes and the body. You feel fully alive. So it’s just a daily discipline,” said Robbins in a recent interview with Thrive Global.

So, while Robbins’ plunge pools aren’t realistic for most of us, a cold shower will do the trick. Here’s how to take a 20-to-30-second cold shower, if you’re wondering how to try it out:

Take your regular warm or hot shower and start to decrease the temperature as you’re ready to get out of the shower (the last minute or so). Face the facet, and allow your body to start adjusting to a cooler temperature by putting your arms in first, and then your legs. Then, decrease the temperature until it’s cold, and move your entire body, including your head, under the facet for a few seconds. The feeling should be freezing and you might have to mentally talk yourself through it the first few times. As Robbins would say, it’s mind over matter.

Last, turn off the tap and get out of the shower. Don’t let your mind trick you into switching on the warm water, or you’ll miss the lasting effects of cold water on your muscles and mind as you start your day

In his book, Power of Habit, Charles Duhigg says it takes two weeks for a habit to stick. So put yourself to the test: if you can get through the first 14 days, you’ll develop some serious mental discipline every single day.

Have you tried the cold water technique? What helps you get motivated in the morning? Tell us in the comments below.

Kristen Marano is a writer based in Toronto, Canada, and Perth, Australia. She’s passionate about connecting women in business to share honest stories and perspectives about the emotional challenges of their work. Follow Kristen on Twitter at Twitter.com/KristenMarano